Microsoft has not yet officially announced May 2019 May update for Windows 10, but the company is already warning about very strange bugs. Microsoft is blocking updates on a USB hard disk with a thumb drive or a computer with an SD card in the SD card reader. "During installation of the May 2019 update, improper drive reallocation may occur on the appropriate computer with an external USB device or SD memory card." Microsoft Support article warns.
In other words, if you have a USB drive with the D: character assigned in Windows, it may have been changed to E: after the May 2019 update. It will not be a big headache for most consumers, but for a tightly managed business machine, changing the drive letter can be a big problem. Microsoft is currently blocking the May 2019 update on computers with this store attached. You must remove the USB or SD depot to complete the upgrade.
Microsoft said that this issue will be resolved in a future Service Update for Windows 10, and will be distributed this May 5 next month It will not be available at the scheduled time. The Windows 10 tester in the release preview ring already has access to the final May 2019 update, and Microsoft is much more cautious about the last test it did.
Due to updates prior to October 2018, it was released for the first time and Microsoft clearly does not want similar issues to be repeated. However, Microsoft detected this USB storage problem when millions of Windows 10 testers solved these flag problems only at the time of the update in late May 2019.